Chapter Exercises

1.

There are errors in the indention in the following code. Fix it to work correctly without errors.

2.

The following code has some syntax errors. There are two errors, but each error is repeated multiple times due to the author copying and pasting lines of code. Fix the errors so that the code runs and draws multiple squares.

3.

Define a function hexagon that has a turtle’s name as its parameter. Your procedure should draw a hexagon (6 sides) where each side has a length of 50. The turtle should end up in its original position and facing. Remember the turns required (exterior angles) for a regular shape are \(360 / numSides\text{.}\)

While you are developing your procedure, we will call the hexagon procedure just once. When you are done, uncomment the code at the bottom of the program to draw 5 more hexagons.

Note 17.9.1.

Turtle procedure reference

# define hexagon here

from turtle import *
brittany = Turtle()
brittany.speed(10)

#Draw one hexagon
hexagon(brittany)

##For fun once hexagon is working - draw 5 more hexagons
#for i in range(5):
#    brittany.right(60)
#    hexagon(brittany)
====
from unittest.gui import TestCaseGui
import re

class myTests(TestCaseGui):
    def countCopies(self, regex):
        matches = re.findall(regex, self.getEditorText())
        return len(matches)

def testOne(self):
        self.assertEqual(self.countCopies("def \w+\s*\(\w+\)"), 1, "Testing that you defined a procedure with one parameter.")
        self.assertGreaterEqual(self.countCopies("\s{4}\w+\.(right|left)\(\d*\)"), 6, "Testing that used enough turns.")
        self.assertGreaterEqual(self.countCopies("\s{4}\w+\.(right|left)\(60\)"), 6, "Testing that each turn was the right amount.")
        self.assertEqual(self.countCopies("\s{4}\w+\.(backward|forward)\(\d*\)"), 6, "Testing that you moved enough times.")
        self.assertEqual(self.countCopies("\s{4}\w+\.(backward|forward)\(50\)"), 6, "Testing that each move was the right length.")

myTests().main()

4.

Complete the body of the function colorRectangle(turtleName, width, colorValue).

It should draw a rectangle that has a width specified by the parameter width and a height of 100. The turtle should be told to draw with a color specified by the parameter colorValue. The turtle should end up in its original position and facing.

Make sure to do pendown and color at the beginning of the procedure and then do penup at the end of the procedure.

There is code in the main part of the program to draw two different color rectangles. Once you get your procedure working, you can comment it out and uncomment the last 4 lines of the program to make a cool pattern.

Note 17.9.2.

Turtle procedure reference

def colorRectangle(turtleName, width, colorValue):
    # height will always be 100
    # your code here

from turtle import *
stu = Turtle()
stu.speed(0)

# test - comment these 3 lines out when done testing
colorRectangle(stu, 50, "light blue")
stu.goto(-100, 0)
colorRectangle(stu, 50, "red")

# fun design - uncomment these lines when done testing
#for i in range(127, 0, -1):
#    hexValue = format(i * 2, '02x')            # change i * 2 into a hexadecimal number
#    colorString = "#" + "00" + (2 * hexValue)  # make a #XXXXXX formatted hex color using no red and two copies  of i*2
#    colorRectangle(stu, i, colorString)
====
from unittest.gui import TestCaseGui
import re

class myTests(TestCaseGui):
    def countCopies(self, regex):
        matches = re.findall(regex, self.getEditorText())
        return len(matches)

def testOne(self):
        self.assertEqual(self.countCopies("\s{4}turtleName.forward\(\s*100\s*\)"), 2, "Testing that you told turtleName to move forward 100 twice (for the height).")
        self.assertEqual(self.countCopies("\s{4}turtleName.forward\(\s*width\s*\)"), 2, "Testing that you turtleName to move forward the right width twice.")
        self.assertEqual(self.countCopies("\s{4}\w+\.(right|left)\(90\)"), 4, "Testing that told turtleName to do four 90 degree turns.")
        self.assertEqual(self.countCopies("\s{4}turtleName.color\s*\(\s*colorValue\s*\)"), 1, "Testing that you told turtleName to use color colorValue.")
        self.assertEqual(self.countCopies("\s{4}turtleName.pendown\("), 1, "Testing that you told turtleName to put down the pen.")
        self.assertEqual(self.countCopies("\s{4}turtleName.penup\("), 1, "Testing that you told turtleName to pick up the pen.")

myTests().main()

Welcome to CS

Exercises 17.9 Chapter Exercises

1.

2.

3.

Note 17.9.1.

4.

Note 17.9.2.